1. Field
One or more embodiments of the present invention relate to a cartridge containing a reagent, a microfluidic device including the cartridge, a method of manufacturing the microfluidic device, and a biochemical analysis method using the microfluidic device.
2. Description of the Related Art
Various methods of analyzing a sample have been developed to, for example, monitor environments, examine food, or diagnose the medical condition of a patient. However, these methods require many manual operations and the use of various devices. To perform an assay or test according to a predetermined protocol, those skilled in the manual operations repeatedly perform various processes including loading of a reagent, mixing, isolating and transporting, reacting, and centrifuging. However, such repeated manual processes result in erroneous results due to “human error.”
To perform tests quickly, skilled clinical pathologists are needed. However, it is hard for even a skilled clinical pathologist to perform various tests at the same time. Even more serious, rapid test results are necessary for timely treatment of emergency patients. Accordingly, analytical equipment enabling the simultaneous, rapid and accurate performing of pathological examinations for given circumstances is desired.
Conventional pathological assays are performed with large and expensive pieces of automated equipment which also require a considerable amount of a sample, such as blood. Moreover, it usually takes days to weeks to obtain results of the pathological assays.
In a small-sized and automated equipment, it is possible to analyze a sample of one patient or, if necessary, plural samples taken from one patient or different patients. An example of such a system involves the use of a microfluidic device, wherein a fluid biological sample such as blood is loaded into a disk-shaped microfluidic device and the disk-shaped microfluidic device is rotated, and then serum can be isolated from blood due to the centrifugal force. The isolated serum is mixed with a predetermined amount of a diluent or a buffer solution and the mixture then flows into a plurality of reaction chambers in the disk-shaped microfluidic device. The reaction chambers usually contain reagents that are loaded prior to allowing the mixture to flow therein. Reagents used may differ according to various purposes. When the serum interacts with different reagents, colors of the mixture may change. The change in color is used to determine if the sample contains a certain component.
However, storing a reagent in a liquid state is difficult. U.S. Pat. No. 5,776,563 discloses a system in which a lyophilized reagent is stored and, when blood analysis is performed, a certain amount of the lyophilized reagent is loaded into reaction chambers of a disk-shaped microfluidic device.